Material for protecting sheets, &amp;c., in tinning.



UNITED STATES PATENT ()FFICE.

JOHN A. KYLE, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO GRANT MOCARGO, OF SAME PLACE.

MATERIAL FOR PROTECTING SHEETS, 800., IN TINNING.

SPECIFICATION forming part of Letters Patent No. 679,972, dated August 6, 1901.

Application filed May 27, 1901. Serial No. 62,073. on. specimens.)

To all whom it may concern: ing and decomposing the natural fats, either Be it known that 1, JOHN A. KYLE, a citivegetable or animal. In treating palm-oil zen of Great Britain, residing at Pittsburg, in palmitic acid and stearic acid are produced the county of Allegheny and State of Pennmingled together. These acids so formed or sylvania, haveinvented or discovered certain produced may be used in their mixed state new and useful Improvements in Material for or separately, the solvent being added there- Protecting Sheets, &c., in Tinning, of which to. The stearic acid can be best produced improvements the followingisa specification. by subjecting the animal fats, preferably tal- In the manufacture of tin and terne sheets low, to saponification and decomposition, as

10 it is necessary to cover the tin or lead bath is well known in the art, and then subjecting with a suitable material which shall protect the resulting acid to pressure to eliminate the the sheets, the tinning-rolls, and also the bath oleic acid or red oil. from oxidation. The material heretofore WhileIinclude underthe term petroleum used and found most suitable for that purany product thereof of the character speci- 15 pose is palm-oil. This material is not only fied-i. e., with a fire test between 400 and expensive, but is objectionable on account of 725 Fahrenheit however obtainedI have its decomposition, which effects a thickening" found it advantageous to produce this solvent of the oil and produces a black ash or residue by boiling down and filtering crude oil until which will choke the bath. I obtained a product having a specific gravity 2o Theobjectof thepresentinventionistoproof about 27.8 Baum and a fire test of 625 vide a material for the purpose specified of Fahrenheit. This boiled-down oil could be such a character as will perform the protecused in most cases alone with the fatty acids tive functions of palm-oil and is also cheaper when manufacturing terne sheets, but in and practically free from oxidation. manufacturing tin sheets, where the temper- 25 The invention is hereinafter more fully deature of the bath is about 600 Fahrenheit, scribed and claimed. more or less, it is found desirable to thin the In the practice of my invention I employ mixture of petroleum product and fatty acid as a principal ingredient of the mixture fatty by adding a distillate of petroleum having a acids which are insoluble in water and are specific gravity of 23.5 Baum and a fire test 30 derived from natural fats, either vegetable of 500 Fahrenheit. The boiled oil and the or animal, and which solidify at or above 68 distillate are mixed in about the proportions Fahrenheit and are practically non-oxidizof seventy-five per cent. of the boiled and able at the melting-point of tin. These fatty twen ty=fi ve per cent. of the distillate, although acids require the addition of some material these proportions may he changed as required 35 to protect them as againstinjurybyhigh heat by circumstances and the temperature at and to maintain them in a sufficiently fluid which the coating occurs. \Vhen using the condition for the purpose at the temperature boiled oil alone as a solvent for the fatty at which the coatingis effected. I have found acid, it is found that a gradual distillation that a petroleum product having a fire test and consequent thickening of the mixture 40 between 400 and 725 Fahrenheit forms a occurs, so that it is necessary to add a little 0 most efficient solvent for the purpose. In of the distillate to bring the mixture to the p manufacturing tin plates the solvent is of a required fluidity. The fatty acid or acids are grade having a fire test of about 500 Fahrenmixed with the solvent in about the proporheit, more or less, while in manufacturing tions of thirty+three per cent; of the fatty 45 terne plates, where the temperature of the acid and sixty-seven per cent. of the solvent; 5' bath is higher, the solvent should have a flre but these proportions may be changed without test of about 700 Fahrenheit, more or less. departing from the spirit of my invention.

Under the general term of fatty acids I While I believe that the fatty acids men= include especially palmitic acid and stearic tioned are those best adapted to the purpose,

5o acid. These acids areobtaihedby saponify- I do not limit myself thereto, but under the terms of the b'road -claims linclude as chem ical equivalents of those specifically mentioned any fatty acids which may have the characteristics stated-i, e., solidifying at or above 68 Fahrenheit and practically nonoxidizable by atmospheric air at the meltingpoint' of tin.

' I claim herein as my invention-- 1. A material for use in coating sheets with metal consisting of a fatty acid solidifying at or above 68 Fahrenheit and practically nonoxidizable by atmospheric air at the meltingpoint of tin and a solvent of the fatty acid,

substantially as set forth.

2. A material for use in coating sheets with metal, consisting of a fatty acid solidifying at or above 68 Fahrenheit and practically nonoxidizable by atmospheric air at the temper- JOHN A. KYLE.

Witnesses DARWIN S. WOLOOTT, F. E. GAITHER. 

